net: af_can: remove useless parameter 'err' in 'can_rx_register()'

Since commit bdfb5765 remove NULL-ptr checks from users of
can_dev_rcv_lists_find(). 'err' parameter is useless, so remove it.

Signed-off-by: Ye Bin <yebin10@huawei.com>
Link: https://lore.kernel.org/all/20221208090940.3695670-1-yebin@huaweicloud.com


Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>